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Numbers k such that every base-5 digit of k is a base-9 digit of k.
7

%I #16 Aug 05 2021 07:00:30

%S 1,2,3,4,11,22,93,121,124,126,156,181,199,317,362,598,750,751,752,755,

%T 756,758,768,770,771,775,776,780,781,785,796,812,831,841,843,849,859,

%U 895,900,906,907,911,912,918,922,927,931,932

%N Numbers k such that every base-5 digit of k is a base-9 digit of k.

%H Reinhard Zumkeller, <a href="/A037396/b037396.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o import Data.List ((\\), nub)

%o a037396 n = a037396_list !! (n-1)

%o a037396_list = filter f [1..] where

%o f x = null $ nub (ds 5 x) \\ nub (ds 9 x)

%o ds b x = if x > 0 then d : ds b x' else [] where (x', d) = divMod x b

%o -- _Reinhard Zumkeller_, May 30 2013

%o (PARI) is(n)=#setminus(Set(digits(n,5)), Set(digits(n,9)))==0 \\ _Charles R Greathouse IV_, Feb 11 2017

%Y Cf. A007091, A007095.

%Y Cf. A037393, A037394, A037395, A037397.

%K nonn,base

%O 1,2

%A _Clark Kimberling_